During a normal contraction, the right ventricle of a heart pumps deoxygenated blood to the lungs and the left ventricle pumps oxygen-enriched blood and nutrients to the organs and blood vessels of the body. Inefficient pumping by the ventricular chambers may result in an inefficient amount of blood pumped to the body and an insufficient amount of fluid being pumped away from the lungs. If the cells of a heart do not receive enough oxygen and nutrients a heart attack can occur.
Certain abnormal ventricular contractions in a patient are sometimes referred to as ventricular ectopy. Exercise-induced ventricular ectopy predicts an increased risk of death for an individual. Dr. Joseph Froklis of the Cleveland Clinic Foundation conducted a study that concluded that post-exercise ventricular ectopy is a better predictor of an increased risk of death than exercise-induced ventricular ectopy. (See Dr. Joseph Froklis et al., “Frequent Ventricular Ectopy after Exercise as a Predictor of Death,” 348 NEJM 781, 781 (2003)). The study defined ventricular ectopy as the presence of seven or more premature beats per minute, ventricular bigeminy or trigeminy, ventricular couplets or triplets, ventricular tachycardia, ventricular flutter, torsade de pointes, or ventricular fibrillation. Post-exercise refers to a period of recovery from exercise when reactivation of parasympathetic heart activity occurs.